Within the overdue Eighties, the sphere of comparative economics and NATO confronted an analogous challenge: the specter of obsolescence. A predictable response of these who had made significant investments in either comparative economics and NATO used to be to seem for a brand new task. It used to be time to claim: comparative monetary structures are useless, lengthy reside comparative fiscal structures.

There's virtually no box in arithmetic which doesn't use Mathe­ matical research. machine equipment in utilized arithmetic, too, are usually in accordance with statements and strategies of Mathematical research. a big a part of Mathematical research is advanced research since it has many purposes in a number of branches of arithmetic.

Extra resources for Analysis of the New Metals. Titanium, Zirconium, Hafnium, Niobium, Tantalum, Tungsten and Their Alloys

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Remove the chloroform layer, and continue as described under Preparation of Calibration Graph. 3. Electrolytic Procedure Dissolve 2 g of the sample in 40 ml of sulphuric acid ( 1 + 4 ) and 2 ml of fluoroboric acid; warm gently to assist solution of the sample. Oxidize the solution with a slight excess of cone, nitric acid, added dropwise, then add a further excess of 5 ml. Boil the solution for 2 - 3 min to expel oxides of nitrogen, cool and dilute to about 300 ml. Heat the cathode (Note 1) at 105°C for 15 min, cool in a desiccator, then weigh.

Dilute 10 ml of this solution to 500 ml. 2. Preparation of Calibration Graphs Graph 1. For Copper Contents 20-800 ppm. Add, separately, 0-5, 1-0, 2 0 , 3 0 and 4 0 ml of the standard copper solution (1 ml = 001 mg Cu) to each of five 50-ml calibrated flasks. Proceed with each solution (and a blank) as follows: Add 8 0 ml of ammonium citrate solution (20%), one drop of neutralred indicator solution (005 %), and shake the solution. Continue to shake, and add sodium hydroxide solution (10%) slowly from a burette until the change-point of the indicator has been reached, then add an excess of 1 0 ml of the sodium hydroxide solution.

Procedure Before weighing, wash all samples with dilute hydrochloric acid (1 + 2), then with water; finally degrease with acetone and dry. To 5 g of the sample, in a polythene beaker, add 50 ml of water, then 5 ml of hydrofluoric acid and successive 5-ml additions of hydrofluoric acid until the sample has dissolved. Oxidize the solution with cone, nitric acid, then add 15 ml of hydrofluoric acid, followed by ammonia solution, slowly, until the pH of the solution is 5. Transfer the solution to a separating funnel (250 ml), add 2 ml of the 2-nitroso-l-naphthol solution, then continue as described under Preparation of Calibration Graph.